Amazon AWS is undeniably the most popular service for sophisticated engineering devops. This is the infrastructure behind some of the most popular and large web applications used by millions. When companies think seriously about their offerings and being able to scale their services, Amazon AWS is the thing in question to use. It has now become quite a staple in terms of its use. As an engineer, you will be required to have a firm understanding of Amazon AWS. Below are some helpful interview questions and answers to get you started. Some of these questions pertain to the more advanced Amazon AWS engineer, who shows experience. And others are a bit more basic. With all interview questions its important you don't copy the language verbatim but instead practice your own set of answers with a close friend.
1. What is AWS?
AWS represents Amazon Web Services. It is a platform that gives secure cloud services, database storage and allows the computing of power and content delivery along with other services to develop different levels in business.
2. What are the main components of AWS?
• Easy E-mail Service: it allows the address of email utilizing Restful API request or through normal SMTP
• Route 53: A DNS web service
• Elastic Compute Cloud (EC2): It provides on demand computing sources for the purposes of hosting. It is very valuable in trouble of some of the variable workloads.
• Identify and Access Management: it gives upgraded protection and identity control for the AWS account.
• Cloud Watch: to observe AWS sources, it gives the managers the ability to inspect and get key. At the same time, one should be able to produce notification alert in a state of crisis.
• Elastic Block Store: it presents sufficient storage masses, which connect to EC2 to allow you to endure data beyond the lifespan of the particular EC2.
3. What is the significance of Buffer in Amazon Web Services?
An elastic load balancer makes sure the incoming traffic is distributed in an optimal manner across different AWS instances. A buffer is going synchronize different components and makes the arrangements additional elastic to a burst of load or traffic. The components would be likely to work in such a way that is unstable for the reception and process of requests. The buffer creates an equilibrium that links the different apparatus and crafts them effort at the identical rate in order to supply rapid services.
4. What is AMI?
The amazon Machine Image is the full form of AMI. It is a template, which gives the information concerning the server, operating system, and applications, which are needed to launch an instance, which is the replica of the AMI running in the cloud as the virtual server. One instance can be launched from different AMIs as the main requirement.
5. Explain the link between an AMI and an instance.
A single Amazon Machine Image can be utilized for launching different instances. The hardware of the host computer utilized by the instance can be defined according to the instance type. Each instance is given according to different capabilities of computing and memory. When the instance has been launched, then it looks like the traditional host and could be interacted like that of the computer.
6. What would be the best way to secure data for carrying in the cloud?
One of the things that have to be ensured is that no one ought to seize the information within the cloud while the data is still moving from one particular point to the next and there should not have to be any leakage with the security key from different storerooms that are in the cloud. The segregation of information from the additional information from companies and the subsequent encryption through the means of approved methods would be one of the options.
7. What does the AWS availability zone mean?
When you would like to collect resources of AWS then one would have to go through the AWS availability zone. When it comes to fault tolerance, appropriately designed applications will have to be designed. So to make sure the fault tolerance is in a proper way the AZs had low latency connections between each other.
8. What are the advantages of AWS to the clients?
AWS is very reliable as a trusted web service from Amazon. It is a secure cloud services platform, which would take the business on a few great levels of success. Customers that operate on a global scale already preferred the AWS platform, solutions and products for building reliable applications that have flexibility and reliability. It is a strong IT infrastructure for the larger scale and smaller enterprises. These questions lie under the categories of the Amazon Support Engineer interview questions and they are very common. That would mean you have to clear the basic first in order to clear the interview.
9. What employment positions are available in amazon web service?
At the present, Amazon is looking to hire product managers, software development engineers, solution architects, support engineers, designers and account managers. If you are seeking Amazon AWS cloud support engineers interview questions, then it would be allows and one of the questions asked by the interviewer for testing the knowledge of the job seekers.
10. What is the definition of scalable when it comes to AWS?
The features of being able to grow in scope, capacity and size when required according to demand would be termed as the best definition in scalable when it comes to amazon web service.
11. State the different layers of cloud computing
• Saas: software as a service
• PaaS: platform as a service
• Iaas: infrastructure as a service
12. How is it possible to vertically scale an amazon instance?
• Twist a fresh large instance than the one which is being governed at the moment
• Delay that instance and the separate the source webs mass of the server and dispatch
• Quit the existing instance and separate the source quantity
• Note the different machine ID and then connect this source mass to the fresh server
13. What is Lambda@edge in AWS?
• In AWS, it is possible to utilize Lambda@Edge utility for solving the problem of low network latency for the end users.
• In Lambda@Edge there would not be a need for provision or managing the servers. It is possible to upload the Node.js code to AWS Lambda and initiate functions that are going to be triggered on the CloudFront requests.
• When a request for the content is attained by CloudFront edge location, then the Lambda code should be ready for implementation.
• This is an optional option for scaling of the operations in CloudFront without the managing of servers.
14. What is the difference between flexibility and scalability?
The aptitude of schemes so that they can enhance the particular tasks on hand on the present hardware resources to grip inconsistency in command is termed as scalability. The ability of the scheme to augment the tasks available on the present and supplementary hardware property would be known as flexibility thus allowing the industry to convene command that does not have the infrastructure at all. AWS has different configuration management solutions, which are concerned with scalability, flexibility, availability and management.
15. What problems are there when you have to access the website with only one particular IP address?
It can lead to minor but impactful issues in front when you suddenly attempt to access the website with one sole internet protocol address. The assumption is that:
• One has to keep on remembering the internet protocol address in order to better use it further during the future.
• When you have to keep remembering the internet protocol address so that you can further use it during the future.
16. What can you say about the term, high availability?
When the desire is accessing a similar thing in AWS with the use of different platforms then this happening may be called high availability. It is in reference to the basic and the advanced procedure of the access of something using the available multiple platforms. In order to better understand it, one has to collect more information concerning the high availability term.
17. How does one bring the website content back to the user when they submit the domain name into the web browser?
Apparently, every website has the unique domain naming system or DNS. That means a unique internet protocol or IP address can be connected to the DNS and each website. The next cases may happen when one wants to submit the domain name into the web browser:
• The web hosting services would then get the input or signal in the form of the request. Following that, the web server hosting company may revert back the request using suitable results to the process.
• When running a browser, it may send a request to the internet protocol address and that IP address is going to be connected automatically to the name of the domain.
• At times the domain naming system may send the IP address back to the user.
• The web browser is going to contact a naming system for bringing back the website content to the users.
18. What are the different event types, which are triggered by Amazon Cloud Front?
• Viewer request: this is when the end user or a particular client program makes a HTTPS/ HTTP request to CloudFront, and so the event is triggered at the Edge Location closer to the end user.
• Origin Request: when the CloudFront server does not have the particular requested object within the cache so the request is forwarded to Origin server. At this time, the event is triggered.
• Viewer Response: when a CloudFront server is ready so it can respond to a request, the event is triggered.
• Origin Response: when the CloudFront server at the Edge location gets the response from Origin server, the event is triggered.
19. Which particular Automation Gears can assist with Spinup Services?
The API tools may be used for the spin-up services as well as, the written scripts. These scripts are done in Perl, bash or the language of preference. There is another option, which entails stipulation tools like an improved descendant. A tool named Scalr may also be utilized and a controlled explanation like Rightscale can be used.
20. How do you construct an AMI?
• Configure an EC2 instance and the attached EBS volumes in the same manner that would want them done in the custom AMI.
• Log out of the instance but do not stop or terminate it.
• Log in to the AWS management console and display the EC2 page for the region and then click; instances.
• Choose the instance from which you want to create a custom AMI.
• Click on ‘actions’ and then on ‘create image’
• Type a name for the Image Name which is identifiable to you then, input text for Image Description
• Click Create Image
• Read the message box, which appears. In order to view the AMI status, go to the AMI page. There it will be possible to see the AMI being created. It may take some time to create the AMI. Plan for 20 minutes or longer if you have installed additional applications or data
21. Why does one utilize common language domain names as opposed to the IP addresses?
The common language domain names are much simpler to remember and communicate which is why it is easier for one to prefer to use common language domain names as opposed to internet protocol addresses.
22. Give a difference between on demand instance and spot instance.
Spot instances are spare and unused EC2 instances that one is able to bid for. Once the bid goes beyond the existing spot price that changes in real time according to demand and supply, then the spot instance is going to be launched. In the event, the spot price becomes more compared to the bid price; the instance is going to go away anytime and could be terminated within a span of 2 minutes of notice. The best way of deciding on the optimal bid price for the spot instance is checking the price history of the previous 90 days, which is available on the AWS console. The advantage of spot instances would be they are very cost effective and the disadvantage is they may be terminated at any time. Spot instances are the ideal when:
• You have a good or flexible workload that can be run when there is sufficient computing capacity
• Tasks, which need extra computing capacity in order to improve the levels of performance
The on demand instances are available at the time when they are needed and there is a need to pay for the time you use them on an hourly basis. These particular instances may be released when they are not needed any more and do not require upfront types of commitments. The availability of these instances is not necessarily guaranteed by AWS, not like the spot instances. The best practice would be launching some on demand instances that can maintain a minimum level of guaranteed compute resources for applying and add-on few spot instances when there is a chance to do so.
23. Give an explanation for TC2 instances.
These instances are particularly designed to give moderate performance and the caliber to burst to a higher level of performance according to the requirements, considering the workload.
24. What is auto scaling?
This is one of the outstanding features within AWS that allows the arrangement and stipulation robotically and the spin up fresh example without involvement from the user. This would be achieved through setting appropriate metrics and brinks to the watch. An example of the selection of the user is configured, spin-up and copied to the collection of the weight planner if you overcome all of the entrances.
25. What is the difference between horizontal and vertical scaling in AWS?
This alludes to the way one would add compute resources to the infrastructure. In vertical scaling more power is added to the current machine though when it comes to horizontal scaling additional resources can be added to the system with the addition of machinery to the network so the workload and processing can be shared among different devices. The best way for one to understand the difference is imagining retiring the old Honda so that you can buy a Mustang because you need more power. That is vertical scaling. The other way to get that much-desired power is not ditching the one car but buying another one. This may be related to horizontal scaling where you can figuratively drive more than one car at the same time. When the users are up to 100, then an EC2 instance would be sufficient to run the entire web application or the database up to the time that traffic increases. Under these circumstances when the traffic goes up, it would be better to vertically scale through the increase of the capacity of the EC2 instance in order to meet the demands of the application. AWS supports instances, which are up to 128 virtual cores, or 488 GB RAM. During the time the users for the application grow to the level of 1000 or more, the vertical scaling may not be able to handle requests and there would be a need for horizontal scaling that is attained through a distributed file system, as well as load balancing and clustering.
26. What are the features of the Amazon EC2 service?
This is a cloud service type meaning it has all of the cloud features. It provides some of the following features.
• Virtual computing environment
• Pre-configured templates for the instances which are the AMIs
• Amazon EC2 gives different configurations of CPU, storage and capacities for networking the instances
• Secure login information for the instances using key pairs as AWS stores the public key and the private keys would be stored in a secure place.
• Storage volumes of the temporary data would be deleted when one stops or terminates the instance
• A firewall that allows you to give specifics on protocols, ports and source IP ranges which can reach the instances with the use of security groups
• Static IP addresses for dynamic cloud computing
• Amazon EC2 gives metadata
• Amazon gives virtual networks logically isolated from the rest of the AWS cloud and that would be optionally connected to the network.
27. Give an explanation of storage for Amazon EC2 instance.
Amazon instance gives a number of data storage alternatives for the instances. Each of the options comes available with a combination of both performance and durability. These storages would be independently used or in combination to suit requirements.
There are four storage types given by AWS
• Amazon EBS: it happens to durable and the block level storage volumes may be attached in running Amazon EC2 instance. The Amazon EBS volume also persists independently from the running life of the Amazon EC2 instance. After the EBS volume is attached to one instance, it is possible to use it in the same way as other physical hard drives. Amazon EBS encryption features also support encryption attributes.
• Amazon S3: amazon S3 gives access to reliable and inexpensive data storage infrastructure. It can be designed for the purpose of making web scale computing to be easier through allowing an individual to store and retrieve any data amount at any time from the Amazon EC2 or any location on the web.
• Adding storage: each time that one launches an instance from an AMI, a root storage device is initiated from that instance. This root storage device has all of the information needed for booting the instance. It is possible to specify storage volumes in addition to the root device when creating an AMI or launch of an instance with the use of block device mapping
• Amazon EC2 Instance Store: Storage disc, which is attached to the host computer, is known as the instance store. The instance storage provides temporary block level storage for the Amazon EC2 instances. The data on the instance store volume persists only during the life of the associated Amazon EC2 instance. If one is to stop or terminate an instance, any data on the instance store volumes is then lost.
28. Discuss stopping, starting and terminating of an Amazon EC2 Instance.
• Stopping and starting an instance: when an instance is stopped, the instance performs the normal type of shut down and then transitions to the stopped state. Every one of the amazon EBS volumes remains attached so that you can begin the instance at a later period. You are not charged for additional instance hours though the instance is in a stopped state.
• Terminating an instance: when an instance is terminated, the instance performs shutdown then the attached Amazon EBS volumes are deleted unless the volume’s deleteOnTermination element is set to false. The instance then is deleted and one can begin the instance all over again at a later time.
29. Explain elastic block storage. What performance may you expect? How possible is it to be backed up? How does one improve on performance?
EBS represents virtualized SAN or the storage area network. That is to mean it is RAID storage to begin with so that would be fault tolerant and redundant. If disks die within that RAID then you do not lose data. It is also virtualized so it is possible to provision and allocate the storage and then it can be attached to the server with different API calls. There is no need to call the storage expert and ask them to run specialized commands from the hardware vendor.
• Performance on EBS may also show some variability. That would mean it could go above the performance of the SLA and then drop below that level. The SLA would allow the average disk I/O rate, which is expected. This would frustrate a number of people such as the performance experts that have the expectation of reliable and consistent disk throughout on the server. In the traditional sense, the hosted servers would behave in this manner as the Virtual AWS instances do not.
• Backup EBS volumes through the snapshot facility through the API call of via the GUI interface such as elasticfox. Improve performance using Linux software raid and striping across the four volumes.
30. What is configuration management and why would you want to utilize it with cloud provisioning of resources?
Configuration management has been there for some time in several web operations as well as, system administration. Though, the cultural popularity of the matter has been limited somewhat. A number of system administrators configure machines like software, which are developed before version control, which is manually making changes on the servers. Each of the servers is slightly unique. Though the process of troubleshooting can be straightforward as one logs into the box and operates directly on it. Configuration management allows for a large automation tool as it manages the servers. This would bring standardization, and appropriate practices as the configurations are managed and version. It also allows for a new method of working that is a very big hurdle to the adoption. Enter the cloud, the configuration management then becomes critical. That is because the virtual servers like the amazon’s EC2 are less reliable when they are compared to the physical ones. One needs such a mechanism in order to rebuild them the way they are at any time. That would push the appropriate practices such as disaster recovery and automation from the center stage.
31. How possible is it to safeguard the EC2 instances on the VPC?
AWS Security groups linked with EC2 instances may assist you to safeguard EC2 instances running in a VPC through giving security at the protocol and port access level. It is possible to configure both INBOUND and OUTBOUND traffic, which allows secured access for the EC2 instance. The AWS security groups are more similar to a firewall as they have certain sets of rules that filter the traffic going in and out of the EC2 instance and deny any form of unauthorized access to the EC2 instances.
32. How many EC2 instances may be utilized within a VPC?
There is a particular limit of running to a total of 20 on demand instances across the instance family. You can purchase 20 reserved instances as well as spot instances considering your dynamic spot limit region.
33. What are the best main practices for security in Amazon EC2?
• Create individual Identity and Access Management users to control access to the AWS recourses. The creation of a separate IAM user provides separate credentials for each user making it possible in order to assign different permissions to each of them according to the access requirements.
• Secure the AWS Root account and the access keys.
• Harden EC2 instances through the disabling of unnecessary devices and applications through only installing the needed software and tools within the EC2 instances.
• Define and review the security group rules regularly.
• Grant the least privileges through opening of permissions required to perform specific tasks and not more than that. Additional permissions may then be granted as required.
• Define and review the security group rules on a regular basis.
• Have a well-defined password policy for each of the users.
• Deploy anti-virus on the AWS network to protect it from Trojans and viruses.
34. What are the significant attributes of the classic load balancer in EC2?
• The high availability feature that makes certain the traffic is distributed among the EC2 instances in the single or multiple availability zones. That makes sure the high scale of availability for incoming traffic.
• The classic load balancer may decide whether to route the traffic or not according to the results of the health check.
• It is possible to implement secure load balancing in a network through the creation of security groups in the VPC.
• The classic load balancer supports sessions, which make certain the traffic from the user is routed to the same instance for a seamless type of experience.
35. What is Redshift?
This is a petabyte-scale data repository service where implementation is easy and cost effective to efficiently investigate the data through employing the current marketing intelligence devices that perform at a high speed and they are controllable.
36. Explain the AWS certificate manager.
The AWS Certificate manager that can be abbreviated to ACM manages the complexity entailing, providing, extending and regulating the certificates granted over ACM to the user’s AWS based forms and websites. People work on ACM to maintain and petition the certificates and practice the other Amazon web services for the website’s purpose. The ACM certificates cannot be handled outside the jurisdiction of AWS.